Multistage reforming with ultra-low pressure cyclic second stage
AssigneeExxon Research & Engineering Co.
InventorsGeorge A. Swan, III, James P. Bailor, David W. Staubs, Eduardo Mon
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Abstract
Disclosed is a process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock. The reforming is conducted in multiple stages with heavy aromatics removal between the first and second stages.
Claims27
A process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock in the presence of hydrogen in a reforming process unit comprised of a plurality of serially connected reactors, wherein each of the reactores contains a supported noble metal-containing reforming catalyst composition, the process comprising:
- (a) conducting the reforming in two or more stages comprised of one or more reactors;
- (b) separating aromatics possessing nine carbon atoms or more from at least a portion of the reaction stream at each stage thereby resulting in a stream rich in C.sub.9 + aromatics and a stream rich in lighter aromatics and paraffins;
- (c) passing at least a portion of the stream rich in lighter aromatics and paraffins to the next downstream stage, in the substantial absence of non-reformed feed;
- and
- (d) wherein the reforming of one or more of the downstream stages is conducted such that at least one of the reactors contains a reforming catalyst selected from (i) a supported mono-metallic or multi-metallic catalyst wherein at least one of the metals is a noble metal, and the support is alumina, and wherein at least one reactor of a downstream stage is operated in the substantial absence of steam, and at a pressure which is at least 25 psig lower than that of the first stage.
A process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock in the presence of hydrogen in a reforming process unit comprised of a plurality of serially connected reactors wherein each of the reactors contains a noble-metal catalyst composition comprised of at least one noble metal, and on alumina support, said process comprising:
- (a) conducting the reforming in two stages which are separated from each other by a heavy aromatics separation unit which accomplishes separation of C.sub.9 + aromatics by fractionation, wherein each stage includes one or more reactors;
- (b) separating, in the heavy aromatics separation unit, at least a portion of the reaction product stream between stages into a C.sub.9 + or C.sub.10 + aromatics-rich stream and a C.sub.9 + or C.sub.10 + aromatics-lean stream, wherein at least a portion of the C.sub.9 + or C.sub.10 + aromatics-lean stream is passed to the next stage, recycled, or collected;
- in the substantial absence of unreformed feed,
- (c) controlling the reforming severity of the first stage to achieve substantial conversion of C.sub.10 + paraffins and naphthenes to aromatics;
- and
- (d) operating the second stage in the substantial absence of steam;
- and at a pressure of at least 25 psig lower than the first stage.
Dependencies are inferred from the claim text.